Delayed metabolic maturation of the cerebral cortex of rat pups derived from lead‐treated dams

Abstract

Rat pups taken from dams exposed to lead (Pb) at concentrations of 0, 5, 30, and 200 mg/l of drinking water from 14 d prior to breeding to 21 d postpartum display evidence of delayed maturation of the cerebral cortex. Delayed maturation was observed as an alteration in the ontogeny of metabolic responses of isolated cerebral tissues taken from rat pups of Pb‐treated dams to elevated K+ concentrations. These responses were found to undergo substantial developmental changes between 6 and 50 d of postnatal age. The delay in development was most marked with respect to the development of the late reduction of NAD(P)1, which occurs in response to an increase of media K+ concentration from 3 to 30 mM. Delays in the development of this response were observed as late as 50 d of age, but assumed the adult pattern by 90 d of age. An increased uptake of oxygen in response to an elevated concentration of K+ provided evidence of metabolic uncoupling in tissues taken from animals at 15 and 21 d of age. At 15 d of age, i...